Measurements

Experimental conditions
Measurements procedure
Measurement Channels
Experiments
Data Analysis

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Experimental conditions

The granite is not glued to the floor
FS = 512Hz
Made by Marc Lesourd on the 12 of January 2018

Measurements procedure

Geophones L-28LB geophones (table tab:L-28LB) are placed on

Marle
Tilt Stage
Top of Hexapod

Natural Frequency [Hz]	4.5
Weight [g]	140
Sensitivity [V/(m/s)]	31.3

L-28LB Geophone characteristics

The structure is excited using an instrumented hammer with impacts on

Marble X-Y-Z
Hexapod X-Y-Z

Measurement Channels

Ch. nb	Element	Location	Direction
1	Hammer	variable
2	Geophone	Marble	X-Y-Z
3	Geophone	Tilt stage	X-Y-Z
4	Geophone	Top of Hexapod	X-Y-Z

Description of each measurement channel

Experiments

Meas. nb	Location	Direction
1	Marble	X
2	Hexapod	X
3	Marble	Y
4	Hexapod	Y
5	Marble	Z
6	Hexapod	Z

Description of the location of direction of the excitation for each measurement

Data Analysis

Loading and pre-processing of the data

Data is scaled and integrated one time to go from velocity to displacement.

  load('./raw_data/freq_frf.mat') % freq_frf

  w = j*2*pi*freq_frf; % j.omega in [rad/s]

  scale_factor = 1;

  load('./raw_data/frf_marble_x.mat') % ReIm1
  frf_marble_x = zeros(size(ReIm1, 1), 3);
  frf_marble_x(:, 1) = -scale_factor*ReIm1(:, 2)./w; % marble_x
  frf_marble_x(:, 2) = -scale_factor*ReIm1(:, 3)./w; % tilt_x
  frf_marble_x(:, 3) = -scale_factor*ReIm1(:, 4)./w; % hexa_x

  load('./raw_data/frf_hexa_x.mat') % ReIm2
  frf_hexa_x = zeros(size(ReIm2, 1), 3);
  frf_hexa_x(:, 1) = -scale_factor*ReIm2(:, 2)./w; % marble_x
  frf_hexa_x(:, 2) = -scale_factor*ReIm2(:, 3)./w; % tilt_x
  frf_hexa_x(:, 3) = -scale_factor*ReIm2(:, 4)./w; % hexa_x

  load('./raw_data/frf_marble_y.mat') % ReIm3
  frf_marble_y = zeros(size(ReIm3, 1), 3);
  frf_marble_y(:, 1) = -scale_factor*ReIm3(:, 2)./w; % marble_y
  frf_marble_y(:, 2) = -scale_factor*ReIm3(:, 3)./w; % tilt_y
  frf_marble_y(:, 3) = -scale_factor*ReIm3(:, 4)./w; % hexa_y

  load('./raw_data/frf_hexa_y.mat') % ReIm4
  frf_hexa_y = zeros(size(ReIm4, 1), 3);
  frf_hexa_y(:, 1) = scale_factor*ReIm4(:, 2)./w; % marble_y
  frf_hexa_y(:, 2) = scale_factor*ReIm4(:, 3)./w; % tilt_y
  frf_hexa_y(:, 3) = scale_factor*ReIm4(:, 4)./w; % hexa_y

  load('./raw_data/frf_marble_z.mat') % ReIm5
  frf_marble_z = zeros(size(ReIm5, 1), 3);
  frf_marble_z(:, 1) = scale_factor*ReIm5(:, 2)./w; % marble_z
  frf_marble_z(:, 2) = scale_factor*ReIm5(:, 3)./w; % tilt_z
  frf_marble_z(:, 3) = scale_factor*ReIm5(:, 4)./w; % hexa_z

  load('./raw_data/frf_hexa_z.mat') % ReIm6
  frf_hexa_z = zeros(size(ReIm6, 1), 3);
  frf_hexa_z(:, 1) = scale_factor*ReIm6(:, 2)./w; % marble_z
  frf_hexa_z(:, 2) = scale_factor*ReIm6(:, 3)./w; % tilt_z
  frf_hexa_z(:, 3) = scale_factor*ReIm6(:, 4)./w; % hexa_z

  load('./raw_data/coher_marble_x.mat') % coh1
  coh_marble_x = zeros(size(coh1, 1), 3);
  coh_marble_x(:, 1) = coh1(:, 2); % marble_x
  coh_marble_x(:, 2) = coh1(:, 3); % tilt_x
  coh_marble_x(:, 3) = coh1(:, 4); % hexa_x

  load('./raw_data/coher_hexa_x.mat') % coh2
  coh_hexa_x = zeros(size(coh2, 1), 3);
  coh_hexa_x(:, 1) = coh2(:, 2); % marble_x
  coh_hexa_x(:, 2) = coh2(:, 3); % tilt_x
  coh_hexa_x(:, 3) = coh2(:, 4); % hexa_x

  load('./raw_data/coher_marble_y.mat') % coh3
  coh_marble_y = zeros(size(coh3, 1), 3);
  coh_marble_y(:, 1) = coh3(:, 2); % marble_y
  coh_marble_y(:, 2) = coh3(:, 3); % tilt_y
  coh_marble_y(:, 3) = coh3(:, 4); % hexa_y

  load('./raw_data/coher_hexa_y.mat') % coh4
  coh_hexa_y = zeros(size(coh4, 1), 3);
  coh_hexa_y(:, 1) = coh4(:, 2); % marble_y
  coh_hexa_y(:, 2) = coh4(:, 3); % tilt_y
  coh_hexa_y(:, 3) = coh4(:, 4); % hexa_y

  load('./raw_data/coher_marble_z.mat') % coh5
  coh_marble_z = zeros(size(coh5, 1), 3);
  coh_marble_z(:, 1) = coh5(:, 2); % marble_z
  coh_marble_z(:, 2) = coh5(:, 3); % tilt_z
  coh_marble_z(:, 3) = coh5(:, 4); % hexa_z

  load('./raw_data/coher_hexa_z.mat') % coh6
  coh_hexa_z = zeros(size(coh6, 1), 3);
  coh_hexa_z(:, 1) = coh6(:, 2); % marble_z
  coh_hexa_z(:, 2) = coh6(:, 3); % tilt_z
  coh_hexa_z(:, 3) = coh6(:, 4); % hexa_z